.TH std::experimental::erase_if(std::unordered_set) 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::experimental::erase_if(std::unordered_set) \- std::experimental::erase_if(std::unordered_set)

.SH Synopsis
   Defined in header <experimental/unordered_set>
   template< class Key, class Hash, class KeyEqual, class
   Alloc, class Pred >                                         (library fundamentals TS
   void erase_if( std::unordered_set<Key, Hash, KeyEqual,      v2)
   Alloc>& c, Pred pred );

   Erases all elements that satisfy the predicate pred from the container. Equivalent
   to

 for (auto i = c.begin(), last = c.end(); i != last;)
 {
     if (pred(*i))
         i = c.erase(i);
     else
         ++i;
 }

.SH Parameters

   c    - container from which to erase
   pred - predicate that determines which elements should be erased

.SH Complexity

   Linear.

.SH Example


// Run this code

 #include <experimental/unordered_set>
 #include <iostream>

 template<typename Os, typename Container>
 inline Os& operator<<(Os& os, Container const& container)
 {
     os << "{ ";
     for (const auto& item : container)
         os << item << ' ';
     return os << '}';
 }

 int main()
 {
     std::unordered_set<int> data{3, 3, 4, 5, 5, 6, 6, 7, 2, 1, 0};
     std::cout << "Original:\\n" << data << '\\n';
     auto divisible_by_3 = [](auto const& x) { return (x % 3) == 0; };
     std::experimental::erase_if(data, divisible_by_3);
     std::cout << "Erase all items divisible by 3:\\n" << data << '\\n';
 }

.SH Possible output:

 Original:
 { 0 1 2 7 6 5 4 3 }
 Erase all items divisible by 3:
 { 1 2 7 5 4 }

.SH See also

   remove    removes elements satisfying specific criteria
   remove_if \fI(function template)\fP

.SH Category:
     * Noindexed pages
